Add the function cmake_expand_imported_targets() to expand imported
targets in a list of libraries into their on-disk file names for a
particular configuration. Adapt the implementation from KDE's
HANDLE_IMPORTED_TARGETS_IN_CMAKE_REQUIRED_LIBRARIES which has been in
use for over 2 years. Call the function from all the Check*.cmake
macros to handle imported targets named in CMAKE_REQUIRED_LIBRARIES.
Alex
Otherwise the compiler may optimize out the reference to the symbol as the
previous version was not really using this. This leads to symbols that are
only in a header but not in the given libraries to be reported as present.
This came up on the first try to fix bug 11333 as "gcc -O3" would optimize
out the reference to pthread_create() so the correct library the symbol is in
was not detected.
The new test code was suggested by Brad King.
The test "complex" sets the variable CMAKE_BACKWARDS_COMPATIBILITY
to 1.4. When that variable is set, configure_file does not default
to IMMEDIATE mode processing. And so, the output file likely does
not exist yet by the time the next line in the CMakeLists.txt file
is processed. When that next line is "try_compile" on that file,
this is a problem.
Fix the problem by explicitly using IMMEDIATE in the configure_file
call.
This problem was quite mysterious, as it only showed up on the
"complex" test, when the previous commit introduced a CheckSymbolExists
call into the FindThreads module. Which is not even explicitly included
in the "complex" test... FindThreads gets included indirectly only
as a side effect of setting CMAKE_BACKWARDS_COMPATIBILITY to 1.4 and
even then it's included indirectly by auto-inclusion of
CMakeBackwardCompatibilityC.cmake...
Wow. Just wow.
The check works for macros, functions, and variables, but not for types
or enumeration values. Clearly describe the behavior of the check with
respect to each symbol type.
This adds copyright/license notification blocks CMake's non-find
modules. Most of the modules had no notices at all. Some had notices
referring to the BSD license already. This commit normalizes existing
notices and adds missing notices.
For example:
CHECK_HEADER_EXISTS("type.h" HAVE_TYPE_H)
is:
CHECK_SYMBOL_EXISTS(main "type.h" HAVE_TYPE_H)
CHECK_LIBRARY_EXISTS("nsl" gethostname HAVE_LIBNSL)
would be
SET(CMAKE_REQUIRED_LIBRARIES "nsl")
CHECK_SYMBOL_EXISTS(gethostname "netdb.h" HAVE_LIBNSL)
...
Alex Neundorf
Rolf Eike Beer
David Cole
Brad King
Todd Gamblin
Ken Martin
Andy Cedilnik
Bill Hoffman